yashsingh1/xdaforums huggingface dataset:
[Epic 4G General] DCRocks:
I have been running EXT2 & EXT4 since they came out. The speed difference has been major, IMO, both on my Moment running EXT2, and my Epic running EXT4.

On my Moment, I never even ran the journaling, though I did turn it back on for my Epic.

IMO, I will never use RFS again, unless I have no other choice. RFS is supposed to be the best for prevention of data loss, but when you turn on journaling with EXT4, you should retain the data protection offered with RFS.

I did have data loss due to frequent power loss (Extended battery for my Epic didnt fit perfectly, and loss connection until I fixed it), but that ended when I turned on journaling.

I have never ran a setup past a couple months, so I can't comment on the long term slowdown, but with just the change from RFS to EXT4 provides a performance increase of the level where I can see the difference in daily use of the phone.
[Epic 4G General] TurboFool:
So, you ran two completely different ROMs with completely different customizations (one, as noted above, was deodexed) and optimizations, and you're just assuming the file system is the reason you're seeing a difference between the two?

As well, did you install all the exact same apps on each, make all the same phone calls, send/receive the same number of text messages, and utilize them in identical manners?

Correlation does not equal causation. Just because one ROM is running one file system and the other another and they perform differently is no evidence on its own that the file system is the cause. Until you eliminate all other outside variables, we've learned absolutely nothing from your experiment. Your test is also subjective, and not blinded. So your personal biases easily slip through, and your assumption that RFS is faster will lead you to use confirmation bias to notice the elements that confirm your supposition and ignore the rest. You'll be more likely to jump to consider the things the RFS-based phone does faster as more important than the ones the EXT4 phone did faster, when the same feature might be in the other list if it was on the system you preferred. This isn't a dig on you, it's a human cognitive bias we all employ that proper scientific tests are designed to avoid. But your test doesn't.

Now I'm not saying EXT4 IS faster, I'm merely saying your test does nothing to tell us one way or the other. As far as I'm aware Google shifted officially to EXT4 as the standard for Gingerbread, and I assume this was done for good reason. That's not to say Samsung didn't have good reason for using RFS that trumped it. But EXT4 is at least a non-proprietary standard that's easier for us to work with, which is one reason some prefer it.
[Epic 4G General] gokuman56:
Well, I can say that the stock rom is odexed, but all the other variables are the same, same amount of apps, I always deleted the texts and call logs, after I saw them or after I received a call. Even then, many people say that EXT4 is much much much faster than RFS, and odexed RFS vs deodexed SFR is not much of a variable difference because one is running stock RFS and one is running an "Stock" EXT4 (now if you know of an odexed EXT4 ROM, then I will gladly try it. But all the other variables were basically the same.
[Epic 4G General] TheDub:
RFS is garbage and even Samsung knows it. They ditched it to go with the more typical EXT4 and I believe Yaffs in some cases (The Yaffs part could admittedly be incorrect, having trouble remembering) in their new products.

Like others have said RFS is basically a form of FAT or FAT32 with Journaling put on top of it. It's an outdated filesystem that was long surpassed by NTFS, HPFS, EXT4, etc.

EXT4 provides dramatically faster I/O which is evident not only in Titanium Backup but the majority of benchmarks that test the I/O performance. Quadrant I believe shows a huge difference for example.

It can also be just as stable as RFS with the use of Journaling. Some ROM's have Journaling On, some off. I think the majority these days have it on because the added stability outweighs the small 2%~ performance gain with it off.
[Epic 4G General] parasense:
I would suggest enabling data=sync or data=journal to get max consistency. Also there is a parameter to control the rate the journal syncs to storage. The faster the better consistency, the worse perf.

Personally id disable ext4 journalling for performance or use ext2, but ext4 has better data structures

Deliver by Epic 4G xda app
[Epic 4G General] epic_me:
I tried ext4 fryo roms with and without jourling on. I would usually after a few days times stat to get force closes and all. I culd only reset my phone and then it would work again for a few days... went back to rfs and on gingerbread rfs quadrant scores are like 1200 to 1300 or so. Rfs is faster under gingerbread as users here report ext4 drops quadrant scores 100 to 200 points from the rfs score now.... go samesung... but I also thought that ext4 was to be th default file system for gingerbreadb
[Epic 4G General] JohnCorleone:
I have never gotten force close or data corruption issues with EXT4 journal on. Now journal off is another story.
[Epic 4G General] ap77:
I find it extremely painful to go back to RFS after EXT4.
[Epic 4G General] IonCannon218:
Totally agree with you on that.

I use EXT4 with Journalling because without journalling I would get instability and force closes.
[Epic 4G General] :
What exactly is RFA, and what's EXT4? I remember EXT2, EXT3, AN EXT4 used to all be partitions on the SD Card that applications were backed up to for easy restore when switching ROMs.
[Epic 4G General] epic_me:
I don't. I don't miss the data coruption even with jourling on. I also noticed rfs with gb is faster then ext4 with gb.
[Epic 4G General] squshy 7:
Well, that's simply because our implementation is messy right now. The latest leak seems to be having that effect on those types of customization.

To the OP...I think you have to remember one important detail.

You were running srf 1.2. A degradation in performance isn't that surprising.

I think you should rerun your test with a completely stock ext4 setup. You could use the ec05 plus kernel, which should provide dual support. And keep it odexed, it really does make a difference. Go do that and see what you find.
[Epic 4G General] chris41g:
I speculate that the degradation in performance is a combination of factors not due to the filesystem, but may be related. One, the major one, will be the buildup and clutter in the dalvik-cache, tombstones, and lost+found directories from running deodexed.

Odex by definition, is an optimized dalvik executable, by deodexing it, we are stripping the optimizations and making it more portable for the sake of customization. Not only are we stripping the optimizations, we are decompiling, and then recompiling without source, and anyone who codes knows that is not always an efficient way of doing things.

Also, these GB kernels and the entire OS has been optimized apparently, to be run on RFS. That wouldn't slow EXT4 down ofcourse, but it speeds RFS up quite a bit. and there isn't any native source to compile EXT4 module from and against, so we are left compiling modules using other devices, or from universal kernel source. We, or I should say I, would prefer to compile the drivers into the kernel.. when we get the source that will happen.

Lastly, people who install custom roms also install a lot of apps, and all those apps cludge up your data and cache partitions, and make it run slow.. rfs or ext4... they also restore data... which causes fcs... rfs or ext4.. but since most custom roms are ext4, the file system gets the blame.

For the record, I'm not for one or the other, and I currently run neither, my epic is bricked... but i was on RFS before that happened... but only by chance...
[Epic 4G General] azyouthinkeyeiz:
Interesting fact: this is all non-sense in our usage. RFS is ROBUST FILE SYSTEM and is Samsung's primary choice for ONEnand flash..

(I know it's already been answered, but this was just ludicrous to me. Did you just google rfs and look for the first one that made sense?)
[Epic 4G General] lviv73:
Check LOST.DIR on the sdcard after using Ext4 for few weeks that folder is about 3-5gb!

So yaeh i think there is greater data loss for ext4 but who cares?Itsnway more snapy.

By the way what exactly is LOST.DIR for?I know that i need to empty it once in a while.

I have speculations about purpose of this folder but dont know for sure.
[Epic 4G General] squshy 7:
It's a folder in which corrupted files land, much like a graveyard. For our purposes, it doesn't neccessarily serve a function. It is possible to open these files, but it takes a lot of guessing of what program to use. Generally not worth your time.
[Epic 4G General] lviv73:
If deodexing is that bad and i know it takes toll on speed then why devs dont reodex their roms?Too lazy/takes too long/too hard or what?

Just odex the rom and leave framework-res,twframework-res and systemUI deodexed for theming-this makes alota sense,why they dont do it like that or have an easy odexing tool out?idk.
[Epic 4G General] lviv73:
Why google have that folder on sdcard so it can steal 5gb off space from average android user that dont know about these things?Thats a good question.

I think google needs to clean up android because its becoming bloated with things that never get used like linux distros.Just check framework-res and systemui and see how many png files are left from older android versions or just simply there for no reason.Like statusbar.png in systemui.apk,why is it there if statusbar color is controled by xml file and not png?

Is google too lazy to clean things up or what?
[Epic 4G General] azyouthinkeyeiz:
Google did not put EXT on the epic.. Lol. That was us. What are you asking?
[Epic 4G General] lviv73:
Im asking because LOST.DIR can fill up 5gb of space on sd card even with rfs after few weeks/months.

Average user gonna wonder where all their space on sdcard went.

Thats what i wondered when my sdcard was full,i deleted all my files and still 7gb shortl,it took me a while to figure out what was taking up 7gb of space on my sdcard.
[Epic 4G General] chris41g:
Things get written to the LOST.DIR when they try to write to the sdcard and don't have perm, or its in the middle of being mounted/unmounted.. or they try to write to a corrupted file on the sdcard. it has nothing to do with the FS on the phone. if you have a lot of space being used in LOST.DIR i recommend a fresh format of your sdcard, and proper mount/unmount procedures when using usb storage on the pc. ie. Safely eject hardware from windows.
[Epic 4G General] lviv73:
I always use proper procedure and always format my sd 3 times from cwm but still.manage to aquire at least 1gb in lost.dir,i cant be the only one.

When formating from cwm what filesystem is used fat/ext4 or rfs?

I always thought it was better to.format from cwm because it probably used native android fs.

Is it better to format sd from windows using fat or ntfs?If so what block size is best 16/32/64?For best performance.
[Epic 4G General] chris41g:
just format fat32 from windows
[Epic 4G General] dwallersv:
I have no explanation other than very rare crashes, wich if probably the reason... I've been running ext4 on Bonsai 4.0.1 for months, no journaling, and haven't had any problems at all.

I'm sure i'm just lucky, and it's a matter of time before disaster, but I thought I'd share my "stable" experience as another datapoint.

I tried enabling journaling using chris41g's CWM flashable script, and it whacked out my file systems. Reason is assumptions about the location/existence of some commands... picked apart the zip, and was able to journal data while booted from a shell cli; need to modify the flashable zip to take care of the other file systems and hyatt have been too lazy to finish it up.

Sent from my mind using telepathitalk
[Epic 4G General] ungovernable1977:
I thought the RFS on GB was pretty snappy...

this discussion AGAIN... it all boils down to benchmarking and ROM marketing to me... RFS has always been fine, has anyone really been able to attribute any REAL WORLD (not benchmarking) 'lag' to RFS??? EXT4 is fine, the only problem was that it creates more writes on the Nand than RFS (search the old threads for the details), so no-journaling was implemented, which is great if you flash every day, but after a while its been pretty obvious most people have issues with data loss, and not just dropping the phone and having the batt fall out. The reboot from power menu was causing it at times, which was usually packed into EXT4 ROMs... whatevs.... If RFS is faster than it used to be with GB, I cant really see anyone complain about it for almost any usage. Yes, your application shortcut list will populate a little slower, boo hoo. Go back to a Berry for a day... get some perspective. I dont really care what people use, but I think people are really just looking for something to excuse the simple e-peen factor... its ok, when OC/UV etc. is common, pushing our phones is obvious, but in reality, theyre damn fast, even with DI18... Personally I like more tweaks like the lockscreen and pulldown mods... these things are whats really cool.... theyre usefull and make iphone users cry. They can always explain away better speed, but not customization... thats androids gold. Ill leave it to engineers to see what they can get make the phone do in a benchmark.
[Epic 4G General] lviv73:
DI18 Syndicate was the fastest and most stable rom to date.
[Epic 4G General] chris41g:
i beg to differ lol... i stand behind eco5plus...
[Epic 4G General] toadlife:
I frequently had data corruption with ext4. Since I decided to stick with stock/rooted/rfs roms I've had almost no data corruption.

As for performance, I haven't perceived a difference.
[Epic 4G General] adelmundo:
Great post. Although benchmark and speeds are great, my iPhone using buddies googoo and gaga over my phone with the mods and customization I can do on my phone. In fact I convinced a friend to also get an Epic from his iPhone 3GS.
[Epic 4G General] DCRocks:
I have, several times, been running a ROM on RFS, then converted to EXT2 or EXT4, and seen improvements in the daily use of the phone's UI. This was much more evident on my Moment than my Epic, but still, in several cases, I was able to actually see the improvement in the use of my phone, regardless of what any benchmark says. Not in every aspect, but in some of the daily things, it did seem to offer a little increase in response.

Agreed. If I had to choose, I would take customization over speed increases any day. My Epic has always been "fast enough", but the tweaks and mods make others go fish-eyed, even other android phone users. Heck, just the SPB Shell 3D launcher on my GF's EVO makes her friends all jealous, forget all the ROM extras her phone now packs.
[Epic 4G General] mkasick:
The most noticeable is the brief period of unresponsiveness shortly after installing/updating an app. I'm sure ext4 has overall better performance, but it's never been compelling enough for me to switch.

Also, I understand phones with MoviNAND controllers (all Galaxy S devices except the Epic) suffer much worse lag, prompting the original lag fixes to the begin with. They're less motivated for the Epic.

I don't recall seeing any I/O statistics illustating this to be the case, and the speculative reasoning behind it is dubious.

Part of ext4's performance improvements are due to its delaying and coalescing of writebacks. I wouldn't be surprised if it generated fewer erase cycles on average.
[Epic 4G General] chris41g:
this.. oneNAND is much more responsive.. and the anti EXT4 crusade was shortlived and misinformed.. while not as necessary especially now, it doesn't hurt anything.. they also tried to say we should disable journaling because the journal writes shortened the life span of the flash device... also nonsense.. while technically anything that writes would shorten its life span, it would be such a small difference it would be immeasurable, and the number of backups and restores you would save just by leaving journaling on by far outweighs the number of writes you save by disabling the journal..

all of these factors are trivial for the epic in comparison to other galaxy s phones though..
[Epic 4G General] JohnCorleone:
I have been using journal on EXT4 since it became available. The only time it has failed on me was when I added apps from a different theme or did something dumb myself.
[Epic 4G General] ungovernable1977:
OK, when the whole back to africa i mean RFS thing started, is when noobnl started the whole thing about wear on the nand, people posting bad blocks, iirc the community generally decided that if there was a difference, that it would only be an issue long after most of us (especially the flash/new device happy) had moved on anyways. The no-journaling thing was created by EXT4 proponents (ACS? cant remember) who wanted to reduce wear on the nand, AND get the speed boost (even more than with journaling on, but not much). Turned out though that a lot of us who used ROMs for weeks (even a month!!) between flashes were getting data corruption, at first written off by 'dude, dont drop your phone and let the batt fall out...' then more realised it was pretty easy for the crap to build up... so people (Rob with midnight notably) made the extra effort to make 2 or even all three options available... now I think we will just have to see with GB how much of an improvement EXT4 is, and as much as I hate saying this 'the market will determine the outcome'. I think the early debate was great, a lot of people learned a lot about how what they were flashing worked, and were given the choice of an informed decision on their modding... im all for choices, as long as its not asking the world for free... but if its simple and doable, let people get the most out of their device relative to their usage. The old threads from when this started are huge, and cover all this... its funny how quick people move on to other devices, or just forget how things happened. Personally ill run RFS or EXT4 with journaling on... whatever... It was just kind of lame early on when you were being forced to switch filesystems just to have a decent ROM, just because that was the flavor of the month tweak.

The only 'lag' that annoys the hell outta me is the media scanning of my SD... Im punished for having 8-10 gigs of music on my phone... really??? It takes FOREVER... and I cannot remember a rom that didnt... some better than others.. thats the only lag I saw as unacceptable.
[Epic 4G General] JohnCorleone:
The post above mine is exactly how I remember things happening. I choose to run EXT4 journal on but I think the choice should be available. If I remember right, Viper used to make all of their ROMs dual RFS and EXT4. I have never had luck with journal off. I didn't like the scare tactics either about bad nand blocks and such regarding EXT4. I am testing so much that I am not using a ROM for months straight without changing BUT before I became a part of ACS I ran Urban Fury for 2+ months straight and didn't have a single force close or any data corruption. That ROM is EXT4 journal on as well. I feel that all ROMs should be journal on but have the journal off zip available. It would eliminate tons of "I am getting force closes" or "I think I got data corruption" posts. It was silly how everything was blamed on not powering down properly or things like that. On the other hand, the devs know a lot more than I do so if they feel its best to release a ROM without journal then that's their choice...I always have my journal on zip handy.
[Epic 4G General] ungovernable1977:
ive got nothing against EXT4, but it always feels 'dirty'... like for some reason, just not right. I think the Red Scare of it was all started like so many things back then by peoples vastly different interpretations of noobnl's posts... theyre so brief and vague they can be read a million ways... so everyone freaked out, I was concerned to, at least enough to keep up with the threads, as I know noobnl is good, but there were posts by very well informed people that basically pointed out that if done right, EXT4 can be fine. I still think a pimped out RFS ROM that can keep up with the EXT4s is nice. I guess I see EXT4 as nitrous... yes it gives you a boost, but it doesnt make the whole car better or faster.

I did take the reluctance to reintroduce journaling on EXT4 as a bit of a bad idea, before we had enough time to confirm it wasnt just quickboots and user error causing data corruption. I didn't like it because a lot of things were moving really fast and really experimental, which is great, but at the time it seemed there werent that many stable ROMs out, except 'old' versions of the ones now cracked out. Which is fine, great actually... its development... but I think we have to remember that XDA is not a hole in the wall anymore, so people considering rooting etc usually end up here pretty quick, I think for the future of keeping phones rootable we need to have some stable ROMs that arent TOO bleeding edge, so the casual android user can have something custom to throw in their iUser friends faces, but not freak out worrying their phone is going to explode. Or worse yet, get spammed with FC's while trying to impress said iPhone user. I dont really care too much about apple.. hate em as much as the next person, I just want to make sure android can stay rootable and 'free' as long as possible, while NOT being relegated to basements and IT departments like the rest of Linux (no offense Linux guys...). In order to do that, we need more users, and a significant userbase who insist on the OPTION to root and customize... you know the rest of the story...
[Epic 4G General] JohnCorleone:
I couldn't agree more. It would be nice to have a ROM that we can refer the people who are new to rooting to that is totally fail proof. Also the ambiguity of Noobnl's posts and the rapid advance in hacks did lead to a lot of confusion and uncertainty among many users. I definately remember all of the RFS/EXT4 and journal on/journal off threads that popped up daily. I have been around here since December and I still can't say with any conviction that my setup is 100% stable for everyone. I have read that over time EXT4 can end up bogging the phone down and that it may be good to periodically wipe the cache to clean things up. I guess that all of us are essentially beta testers even on ROMs that are final releases. I can't imagine that Samsung didn't research and thoroughly test to see what was the best file system for our phone at the time. That being said, I went into this knowing that issues may pop up on occasion but I just couldn't resist trying to get every bit of performance out of my phone that was possible. I do know this...my phone is many times better now than when I got it and I am more happy with my 2 daily setups than I have ever been since I got my phone on launch day.
[Epic 4G General] ghostrid3r:
I likes my coffee with RFS or EXT4 journaling ON. Never was one to advocate EXT4 OFF, even for sake of e-peenor scores or small speed boost. :p

Stability > Speed
[Epic 4G General] mattallica76:
One thing you might try is to drop a ".nomedia" file into any directories you don't want scanned by the media scanner on your SDCard. This will speed up the overall scan time. The OS does this by default in some directories, and Bonsai actually adds a few more of them, but you can always add them yourself as well.